Hot line connector

ABSTRACT

A hot line connector for firmly attaching a tap-off conductor to a high voltage line in which there are clamping jaws with an improved interposed spacer having insulation piercing teeth adapted to pierce insulation and make flat contact with line to insure full mechanical contact, adequate electrical connection between the line and the conductor.

United States Patent 1 91 1111 3,923,363

Kraft 1 Dec. 2, 1975 15 1 HOT LINE CONNECTOR 3,132,914 5/1964 Wengen339/109 3,425,028 l/l969 Neaderland.... 339/95 R [75] mentor: KraftHPewel1 3,426,319 2/1969 Downs et al. 339/272 R Juncflon 3,760,3419/1973 Grad 339/272 R [73] Assignee: Fargo Mfg. Company, Inc.,

Poughkeepsie, NY. Primary Examiner loseph H. McGlynn [22] Filed: Aug.16, 1974 1 1 pp 497,894 57 ABSTRACT A hot line connector for firmlyattaching a tap-off ?g gZ conductor to a high voltage line in whichthere are Fieid "55 97 99 clamping jaws with an improved interposedspacer 264 having insulation piercing teeth adapted to pierce insulationand make flat contact with line to insure full mechanical contact,adequate electrical connection [56] uNlTEg g a A g gs gzfrENTs betweenthe line and the conductor.

2,096,796 10/1937 Dunaway .7 339/109 1 Claim, 7 Drawing Figures "m llU.S. Patant Dec. 2, 1975 Sheet 1 of 4 3,923,363

U.S. Patent Dec. 2, 1975 Sheet 2 of4 3,923,363

US. Patent Dec. 2, 1975 Sheet 3 (f4 3,923,363

FIG. 5

Sheet 4 of 4 3,923,363

Patent Dec. 2, 1975 HOT LINE CONNECTOR BACKGROUND OF THE INVENTION Thisinvention relates to a functionally and structurally improved connectorassembly intended to connect tap-off conductors with transmission lines.

Pat. No. 3,132,914 describes and claims a clamp assembly of the typedescribed and claimed herein. The connector of the present inventionembodies improvements to the clamp assembly of that patent including tworing type clamps for firmly securing the tap conductor to the lower jaw,an elastic removable band for detachably holding the spacer bar to theconnector assembly, and insulation piercing teeth embedded in the spacerbar adapted to pierce the insulation and mushroom against the metalconductor for a full contact electrical connection.

SUMMARY OF THE INVENTION It is a primary object of the invention toprovide an assembly in which the tap-off conductor may be firmly securedto permanent parts thereof in a manner such that the linesman need notfear that an accidental uncoupling of the tap-off will occur at the timehe is manipulating the assembly to associate it with a hot ortransmission line; the conductor remaining as a permanent part of theassembly throughout the entire life of the latter.

A further object is that of providing an assembly which may readily bemanipulated by the linesman and which may be manufactured at nominalcost.

Moreover, by the present teachings, a structure is furnished such thatthe clamp may readily be electrically connected with or disconnectedfrom a transmission line without danger of damage to the latter incidentto arcing or similar causes.

It is a further object to provide an assembly in which insulationpiercing teeth are embodied within the assembly to pierce the insulationand mushroom against the metal line to insure a full contact, adquateelectrical connection between the transmission line and the tap-offconductor.

It is a further object to provide an assembly in which a spacer bar isreadily detachable from the assembly to permit such bar, when locked tothe transmission line, to be re-connected to a connector assembly.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects and advantages willbecome apparent from the following description which is to be taken inconjunction with the accompanying drawings, in which:

FIG. 1 is an exploded or separated view of the connector of the presentinvention showing the various components;

FIG. 2 is a rear elevation of the connector in applied position;

FIG. 3 is a top view;

FIG. 4 is a front view;

FIG. 5 is a side view;

FIG. 6 is a front view, partly broken away and in section, showing amodified type of connector with additional insulation piercing teeth;

FIG. 7 is a sectional view taken along the line 77 of FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, inFIG. 2 the reference numeral 10 indicated a hot or transmission line and11 one form of the tap-off conductor. As shown especially in FIG. 1, theassembly will include a main clamp involving an upper jaw 12 and a lowerjaw 13. These jaws are disposed in opposed relationship and aremaintained in this position by conveniently providing as part of thelower jaw a rearwardly extending casing portion 14 the interior of whichdefines in plan a rectangular space. Within that space a block 15 isslidably disposed to be guided by engagement with the adjacent faces ofthe casing structure 14 and is integral with jaw 12. It is formed with athreaded bore 16 into which the correspondingly threaded shank 16 of aneye-bolt 17 extends. That bolt mounts a collar 18 fixed with respect toits shank and rotatably bearing against the lower face of casing 14.

Downwardly extending portions 19 are conveniently included as part ofthe casing structure 14 and lie one to each side of the bolt shank. Theopening in the lower portion of casing 14 and through which the boltshank extends is unthreaded. Pins 20 may be mounted on each side of theextended portions 19 to underlie the collar 18. It is, of course,apparent that in lieu of an eye-type bolt alternative units may besubstituted. However, it is in many respects preferred to utilize a boltof this type in that it lends itself to the techniques commonly employedby linesmen in connection with the mounting of assemblies by the use ofa hot-line stick. It is also preferred as part of the assembly to employa spacer bar 21 intervening the jaws 12 and 13. These bars beingpreferably made of pure aluminum, they provide a short, high conductivepath between the transmission line and conductor 11 or its equivalent.This bar has rearwardly extending hook-shaped parts 22 on to which maybe hooked an elastic band 23 to hold the spacer in position and to alloweasy removal. These hook-shaped parts 22 overlap the side edges offlange portions 24 to conveniently hold the bar against unnecessaryshifting. Also it is preferred that the upper jaw 12 be defined by adownwardly and forwardly extending lip 25. The rectangular channel ofthe casing portion 14 is provided with a slot 14a in which rides a screwmember 15a screwed into the block 15. This further serves to align theblock with the channel and prevent their separation if the eye-bolt 17is removed from the block.

Now with a view to securing conductor 1 1 against detachment from theassembly, it will be observed that in the the present exemplificationlower jaw 13 is provided with extensions 26 projecting laterally beyondthe plane into which upper jaw 12 extends. This extension, as in FIGS. 1and 2, provides a lower jaw in the form of a grooved and narrowedportion 27 coextensive with jaw 13 which receives the conductor engagedby that lower jaw. Portions 27 are provided with cross members 28 at theends of the conductor receiving channel. The narrowed portions 27 of theextensions 26 are sized and adapted to receive tap clamps 29 each ofwhich has a generally key-hole shaped channel 30 running through it. Thelower portion of the channel fits the portion 27 of the extension 26while the upper portion of the channel is shaped to receive conductorsof different diameters. The base of the channel 30 has a threaded bore31 to receive the correspondingly threaded bolt 32 having a head 33. Thebolt 32 can be screwed against the bottom of the grooved portion 27 ofthe extension 26 to clamp the conductor firmly against the top of thechannel 30. With the clamps 29 on each side tightened the conductor willbe held securely against displacement from the lower jaw 13. Theassembly may thereupon be associated with a transmission line 10.

With the conductor 11 thus secrued to the lower jaw 13 by the clamps 29,the connector is now ready for application to the transmission line 10.Ordinarily a linesman will employ a hot stick which he will couple withthe end 17 of bolt 16 to elevate the assembly. As a consequence ofpreferably employing an extended lip portion 25, no difficulty will beexperienced by the operator in hooking the assembly into position.Thereafter, by rotating bolt 16, jaws 12 and 13 will be drawn towardseach other so that these jaws will intimately engage cable and conductor11, with the intervening spacer bar pressed into firm contact with thefaces of these lines. With this disposition of the parts established,then the hot stick may be uncoupled from the assembly and a propertap-off will have been provided.

To insure full contact between the insulated line 10 and the conductor11 a series of insulation piercing teeth 34 are embedded in the uppergroove of the spacer bar 21. These teeth pierce the insulation sheathwhen the connector tightening torque is applied. These teeth are mountedin the spacer bar and are preferably made from a softer material thanthe pad itself. This softer material allows the teeth to pierce theinsulation, contact the metal conductor and then flow along it ratherthan to penetrate it. This results in a flattened, full contact,adequate electrical connection. In turn the flattened teeth, mushroomedas they are, within the insulation prevent backout of the teeth if theconnector is to be removed. Consequently, the pressure spacer pad,because of its removable, flexible rubber band attachment, separatesfrom the connector and stays in location on the run conductor- 10. Withthe pad so locked, easy re-connection can be made by the connector tothe pressure pad without further puncturing of the insulation.

The piercing teeth 34 have a geometry to pierce insulation and hardnessless than that of the conductor strands causing teeth to fold overstrands increasing contact area and locking under uncut insulation. Thisallows the possibility of transferring relatively high cur rents asteeth can be added for more contact area without damaging run conductor.The connector in such case will in effect be a one-shot device, becausewith the mushrooming attachment the connector is locked to the conductorand can only be removed by tearing the piercing holes.

It will be understood that additional teeth may be provided to increasethe contact between the connector and the line 10 and the connector andthe conductor 11. FIGS. 6 and 7 illustrate another series of teeth 35 inthe groove of the upper jaw 12. If necessary or desirable similar teethcould also be added to the lower groove of the spacer 21 or the grooveof the lower jaw 13.

Thus, among others, the several objects of the invention as specificallyaforenoted are achieved. Obviously, numerous changes in construction andrearrangement of the parts may be resorted to without departing from thespirit of the invention as defined by the claims.

' What is claimed is:

1. In a connector assembly for attaching a tap-off conductor to aninsulation sheathed high voltage line of the type including upper andlower clamping jaws and first attachment means connecting said upper andlower jaws with said upper jaw shiftable toward and away from said lowerjaw and first shifting means forming a part of said first attachmentmeans for shifting said upper jaw toward and away from said lower jawthat improvement comprising:

alignment means for initially aligning said tap-off conductor withrespect to said clamping jaws;

a conductor spacer bar supported between said jaws and shiftabletherebetween which conductor bar is detachably affixed to the assemblyand is provided with insulation piercing teeth positioned to pierce theinsulation of the high voltage line;

said alignment means including a lateral extension on each side of saidlower jaw, which lower jaw and said lateral extensions provide anelongated seat for the tap-off conductor extending beneath the conductorbar;

tap conductor clamps shaped to receive the said lateral extensions andthe tap-off conductor .and having means for fastening said tap-offconductor to said assembly with said tap-off conductor held on each sideof said lower jaw and beneath said conductor bar;

whereby said assembly can be attached to said high voltage line withsaid high voltage line between said upper jaw and said conductor bar andsaid upper and lower jaws can be brought toward each other by said firstshifting means with said high voltage line and said tap-off conductorengaging said conductor bar in clamped relation with the teeth of theconductor bar piercing the insulation of the high voltage line and thetap-off conductor engaging said conductor bar in clamped relation toform a full contact electrical connection between the high voltage lineand tap-off conductor; and said insulation piercing teeth made of ahardness less than that of the strands of the high voltage line to allowthe teeth to pierce the insulation sheath of the high voltage line andmushroom under pressure against the said strands to make a flattened,full contact, adequate electrical connection between the conductor barand the high voltage line.

1. In a connector assembly for attaching a tap-off conductor to aninsulation sheathed high voltage line of the type including upper andlower clamping jaws and first attachment means connecting said upper andlower jaws with said upper jaw shiftable toward and away from said lowerjaw and first shifting means forming a part of said first attachmentmeans for shifting said upper jaw toward and away from said lower jawthat improvement comprising: alignment means for initially aligning saidtap-off conductor with respect to said clamping jaws; a conductor spacerbar supported between said jaws and shiftable therebetween whichconductor bar is detachably affixed to the assembly and is provided withinsulation piercing teeth positioned to pierce the insulation of thehigh voltage line; said alignment means including a lateral extension oneach side of said lower jaw, which lower jaw and said lateral extensionsprovide an elongated seat for the tap-off conductor extending beneaththe conductor bar; tap conductor clamps shaped to receive the saidlateral extensions and the tap-off conductor and having means forfastening said tap-off conductor to said assembly with said tap-offconductor held on each side of said lower jaw and beneath said conductorbar; whereby said assembly can be attacHed to said high voltage linewith said high voltage line between said upper jaw and said conductorbar and said upper and lower jaws can be brought toward each other bysaid first shifting means with said high voltage line and said tap-offconductor engaging said conductor bar in clamped relation with the teethof the conductor bar piercing the insulation of the high voltage lineand the tapoff conductor engaging said conductor bar in clamped relationto form a full contact electrical connection between the high voltageline and tap-off conductor; and said insulation piercing teeth made of ahardness less than that of the strands of the high voltage line to allowthe teeth to pierce the insulation sheath of the high voltage line andmushroom under pressure against the said strands to make a flattened,full contact, adequate electrical connection between the conductor barand the high voltage line.